This invention relates to a combination product for combined use in induction of labor or termination of pregnancy.
To avert danger to mother and/or child, it is sometimes necessary to induce birth artificially or prematurely terminate pregnancy. Surgical techniques and pharmacological methods are available for this purpose.
A good pharmacological method is vaginal or intramuscular application of prostaglandins. This is used if pregnancy is terminated in the 1st or 2nd trimester of the pregnancy (Contraception 1983, Vol. 27, 51-60, and Int. J. Gynaecol. Obstet. 1982, Vol. 20, 383-386). The advantages of prostaglandins include the ease of application and the ability to use them over a long period of pregnancy. The disadvantages of prostaglandins include acute side effects such as pains and nausea; moreover, the success rate in the case of termination of pregnancy in advanced phases of pregnancy is not more than 90%, even after lengthy treatment with prostaglandins.
Another possibility of terminating a pregnancy is to apply an antigestagen (Med. et Hyg. 1982, Vol. 40, 2087-2093). Antigestagens are tolerated better than prostaglandins, but compared with prostaglandins they have greater latency and individual variability with regard to the commencement of effect. In animal tests, in which muscular effects on the uterus play a decisive role, they trigger abortions with a latency of several days. In these tests, some antigestagens otherwise very effective, are effective in only a portion of the animals, even at the highest dosages tested.
In German patent application P 33 37 450.3 (U.S. Ser. No. 660,358 of Oct. 12, 1984, which disclosure is incorporated by reference herein), there is a description of how disadvantages typical of PG and AG can be avoided by using prostaglandins (PG) and antigestagens (AG) jointly for termination of pregnancy. In this connection, the amounts of prostaglandin and antigestagen when used in combination can be considerably reduced in comparison to the customary amounts, it being possible to increase the success rate of terminations of pregnancy even more.